Verizon Wireless has confirmed that the carrier is testing the Internet Multimedia Subsystem network overlay and backend enhancement on its current 3G network. The enhancement allows voice calls to be carried as data calls instead of being sent over the circuit-switched voice network

The subsystem is being selected as the voice call carrier for its forthcoming LTE network due to its popularity across various CDMA carriers for its ease of integration across different network overlays and has also confirmed that its legacy CDMA 1xRTT network will still be maintained and active for a decade after the initial deployment of the LTE network.